Techniques for inserting advertising content and other personalized information into media assets are described. The techniques involve inserting personalized ads and other content into media assets as a server at the content delivery network (CDN) point-of-presence (POP) is performing the individualized encoding of the file on-the-fly. The ads and other content can be personalized based on the user's purchasing habits, user's location (geographic, GPS, IP location, etc.), the content in the media file and the like. In addition, the ads can be inserted into specific parts of the video (i.e. key frames, key slices, etc.) because the CDN node is actually transcoding the content and thus can insert the ads into the content in its own native format. For example, ads can appear as part of the video itself, different language subtitles can be integrated into the video based on the location of the user, and the like.